Home / DIYs / HID vs LED for Cars – Which is Better?


B7 Clear Corner Mod Complete

I have a number of posts on my blog about upgrading your existing halogen bulbs to either HID (Xenon) bulbs for headlights or fog lights, as well as a number of articles on upgrading to LED bulbs for smaller things like DRLs, Reverse Bulbs, and City Lights. A commenter recently asked why I recommend HID vs LED setups depending on the bulb, which is a great question! Both LED and HID headlights have gained popularity in recent years because they offer the appeal of advance technology and high performance, as compared to traditional halogen bulbs. Whereas halogen bulbs more closely resemble the type of household bulbs that you would have at home, both LED and HID headlights use sophisticated technology to light your path. Both are good options for your vehicle, but there are some differences bear noting when choosing between the two. Let’s look at LED vs HID headlights and compare the two options throughout the rest of this post to understand when one option is better than the other.

Benefits of HID Lights

B7 S4 HID Fogs - Before & After

Also known as xenon headlights, HID (or high intensity charge bulbs) feature an arc of electricity created by electricity travelling between two tungsten electrodes inside the bulb, which is filled with xenon gas. The result is a brighter light than you get from a tungsten element alone. To put that into perspective, you can get about 3,000 lumens (a unit measuring the amount of light emitted per second) from an HID bulb, whereas a halogen bulb emits just about half that amount, for a difference of 90 square meters vs. 30 square meters of illumination. That results in better night driving visibility and increased safety, even in bad weather. HID bulbs also use much less energy than halogen bulbs and last much longer than halogen bulbs – 2000 hours of illumination as opposed to just 450. On the downside, HID lights are rather expensive when compared to other types of lights and because they are uniquely shaped, it can be difficult to retrofit an older car with these bulbs.


  • Far brighter light, and a cooler color than halogen
  • Far less energy consumption than halogen
  • Longer lasting that halogen


  • Bigger shape than halogen (may not fit)
  • Needs a projector lens to focus beam or may blind oncoming drivers
  • Requires a ballast to power it (needs room to mount)
  • May need a coding update to your ECU

Benefits of LED lights

LED DRL for B7 Audi A4 & S4

LED bulbs are relatively new on the automotive lighting scene, but they have gained huge popularity in recent years. LEDs are electrical conductors that emit light when they are turned on by way of an electrical circuit. The circuit is either switched on or it is off; these bulbs do not require a heating up period. One of the biggest advantages in favor of LED headlights is that they have very few parts. That means they can be made quite small and can withstand any vibrations and bumps that may occur on rough roads. They, too, consume less energy than halogen bulbs and are very long-lasting, sometimes up to tens of thousands of hours. One of the most popular reasons for choosing LED bulbs is that they come in many different colors of light.


  • Brighter than halogen, but less bright than HID
  • More color options than halogen or HID, option for strobe lighting
  • Less energy consumption than halogen
  • Longer lasting than halogen
  • Smaller, easier to fit shape than HID
  • No ballast required


  • May require resistors to avoid a “bulb out” error on dash
  • Light does not project as far

When to Pick HID over LED?

LED DRLs in B7 Headlights

LEDs are cheaper, smaller, don’t need a special ballast or projector lens, and have more color options, which makes them the ideal choice for replacing smaller bulbs like turn signals, reverse lights, or reverse lights…but for lights that you need a longer field of vision, like your headlights, fog lights, or a separate spot light (i.e. on a roof or separate light rail) HIDs are the way to go. Automakers are now making LEDs that work well as a main headlight beam or fog light beam, but that technology is very expensive and requires special wiring and headlight lenses that can’t be easily retrofitted, so for now this technology isn’t obtainable unless your car also came with a OEM LED headlight/fog light option.

TL;DR: if it’s a smaller bulb, go LED. If it’s your headlights or fog lights, go for a HID kit. Anything in between, research your options and see what is the most cost-effective.


About the author: Nick Roshon


Nick has been an Audi owner and fanatic for the last 10 years, and started Nick's Car Blog in 2009 to share DIYs and pictures of his A4. Currently he drives a 2012 Audi TT-RS, and has previously owned a B7 S4, B7 A4, and an 82 Audi Coupe (GT) LeMons race car. In his day job, Nick is a digital marketer and lives in San Diego, CA, USA.


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  1. Hey nick I have a b7 a4 2.0t and the dealer says that I have the upper booster leak on the turbo to fix it they told me is 2500 to replace the turbo any recommendations to fix that problem with out cost me a leg and arm thanks

  2. Hi Grover – I’d start by finding an independent Audi/VW mechanic to both get a second opinion, as well as a second price quote. “Upper booster leak” isn’t something I’ve heard before, but it’s possible that the turbo isn’t bad and its just a component – if not, you can usually get a rebuilt turbo for cheaper, or if you’re going to spend that kind of money on it, you might want to consider a K04 or JHM Big Turbo upgrade: http://nickscarblog.com/reviews/jhm-stage-3-big-turbo-kit-for-the-b7-audi-a4-2-0t

  3. What bubls did you buy for the day time lights?

  4. My car is using HID bulbs for headlights and fog lights, but using halogen bulbs for turn signals. I guess I should replace turn signals with LED bulbs. Thanks for your valuable information!

  5. For me, me LEDs on my S3 look cheap and not as expensive. I feel like they look like a common Kia coming down the road. I don’t know if that is because I am so use to HID or Xenons being the “luxury” look or not. But, that is just my opinion. They are much “whiter”, but feel cheaper–even though there is an uncharge for that package. Any thoughts?

  6. They’ve definitely become a lot more common these days, but I still prefer the look to the yellowish halogen bulbs.

  7. I haven’t had any luck doing LEDs in the turn signal bulbs on my car, the Audi/VW system is really finicky about those for some reason…but worth a shot, just not sure what resistors to advise.

  8. do the HIDs get hot like household halogens do? I would think that would have some sort of effect long term?

  9. The ballasts get hotter than the bulbs, the bulbs are pretty reasonable. Make sure the ballasts are mounted somewhere appropriate, but bulb to bulb it should be fine…

  10. Right now where I live the regulations are very harsh about HID lights so my default is go for LED lights… but I like the pros and cons comparison you made, very illustrative.

  11. In my fog lights….I thought the yellow or orange like light color would be better for fog or snow. Bright white lights does not do well in Foggy weather, in my driving experience. That is why my head lights does not work as well as my fog lights.

  12. Thanks for the article, Nick. A little silly but, you really would go HID for headlights (since it sounds like you feel like look more … expensive and have a longer view distance)? And maybe LEDs for fog lamps? – We just bought a Mini convertible for my wife.

  13. Thinking about installing HIDs in my ’10 genesis coupe. Because of the beam difference, is the projector something that can be bought and given to the person installing the lights or what is that about…I know halogen bulbs normally have their own housing, so how much will HIDs affect that?

  14. I’d go HIDs for headlights definitely. For fog lights I’d probably still go HID – the LEDs don’t really project the light a very far distance, they’re better suited for DRLs, turn signals, etc…unless you get an aftermarket housing and LED that is high powered and meant for fog light use, of course.

  15. Yeah, you can either buy OEM housings for a ’10 genesis coupe that had HIDs from the factory, and they’ll have projectors built in, or you could retrofit the projectors within your halogen housing using kits like the ones from here: https://www.theretrofitsource.com/

  16. Hey Nick, you need to re-do this write up! I have LED bulbs that are plug and play with heat dissipating fans that plug into my factory headlights of my GMC Canyon and they are the best light output of anything I have ever driven and the color is perfect crisp blue/white. Still no way to convert factory HID to LED which is a bummer but I plan to swap my factory B6 D1S headlights for some DEPO H7 Halogen units just so I can run the LED bulbs I have in my truck! They are outstanding and quality has been good so far. I paid $28 for a pair of low beam bulbs for my truck and they are absolutely fantastic! Not to mention when you turn on the lights, they are instant full brightness. I would come back and revise your write up and test out these bulbs on a halogen B7


  17. Hi Evan – interesting, thanks for the info! Let me know how it goes on the B6, I’m curious if they through a headlight error in the dash or not.

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